Darren Neate, 32, came off his motorbike and died after a crash on June 8.
After his death Doctor Ellie Pierce took to social media in an online post shared dozens of times.
She describing his injuries as “gory” and wrote: “The thing going on in my mind at this moment? Not was there something that I could have done, because there wasn’t.
“But why the bloody hell wasn’t he wearing a crash helmet? It’s not a fashion statement, it’s because they save lives! This person learned the hard way.”
She ended the post, which didn’t mention Darren by name, urging motorcyclists to wear a crash helmet. The post was later deleted.
Darren’s mother Charmaine Neate had asked doctors at Doncaster Royal Infirmary, not to go into details about her son’s injuries because she thought it would be too distressing.
The family have now criticised Dr Pierce’s actions and family friend Leaona Scully said seeing the Facebook message left them feeling sick and “traumatised”.
Ms Scully, 27, said: “The family are struggling to come to terms with losing Darren as it is, and this has just made things so much worse for them.
“She’s a medical professional with a duty of care, so why was she even talking about this on Facebook. It’s just so unprofessional, I really think she should apologise as well.
“The thing that the family ﬁnd the hardest about what she wrote is the fact that she says she wasn’t thinking of his care when she was there, but that he should have been wearing a crash helmet.”
Richard Parker, director of nursing, midwifery and quality at the Doncaster and Bassetlaw Hospitals NHS Foundation Trust, said: “We were made aware of the comment posted on Facebook by one of our junior doctors and we can confirm that action was taken immediately by a senior consultant.
“I am aware of the distress that this has caused the family at this time and have spoken to them and offered unreserved apologies on behalf of the Trust and the junior doctor involved.
“I have made clear to the family that these comments do not in any way represent the views and values of the organisation, and that the junior doctor completely accepts that the post was inappropriate and immediately removed the message on realising their mistake.”